问题补充:
—What were you doing when he “hello”to you?
—I in front of the blackboard.
A. was saying; read
B. was saying; was reading
C. said; read
D. said; was reading
答案:
A. was saying; read
B. was saying; was reading
C. said; read
(答案→)D. said; was reading
解析:句意:当他跟你打招呼时你在做什么?我正在黑板前读书。根据主句的时态为过去进行时可知When引导的时间状语从句用一般过去时,回答用过去进行时;故选D。